[Asterisk-Users] Power Failure, Line Switch, Relay device

[Shawn L. Djernes]

Hello List,

Does anyone know of a device that works with the TDM400P FXO/FXS Modules to
provide line backup for power failure?

I have an idea for such a device but do not have enough vision to do the
soldering of the parts.

My ideal device would be able to sense when asterisk has brought the FXS
port up and then switch a relay over so that the phone was connected to the
FXS interface.  Then if the FXS or asterisk failed for any reason and the
line was dead the relay would drop into default state connecting the phone
to the external PSTN trunk.

Now for the reason I need such a device.

My Girlfriend has CP and cannot manually manipulate phone lines to switch a
cable if the asterisk box were to go down. Also once she is in bed, she can
not get up by herself to get to another phone.  I know there the Sipura 3000
does auto line fail over but from discussions with a couple people who have
them.  The sound quality is bad and the line fail over reverses the polarity
and makes the Nortel phones unhappy.

If someone has a suggestion for a place to buy such a device or wants to
build a prototype for me to test I would appreciate it.

Thanks,
Shawn